716 THE AMERICAN NATURALIST.  [Vol. XXXIII. 
G. Latreutes Stimpson. First pair of feet with exopodites, carapax with 
a median spine. 
. L. ensiferus (M.-Edw.) Stm. Gulf weed 
G. noh oivi dilapi. Four anterior pairs of feet with exopodites, 
carpus of second triarticulate. 
. R. parvulus Stm. Texas 
G. Concorde Kingnley. Sauk very hoU carpus of second pair 
biarticulate. 
45. C. gibberosa Kinsley M, Fig. 17 
Family ATYIDA. Fi irst two pairs of feet nearly equal, carpus of second 
pair not annulate. 
Sub-family ATYINA. 
G. Caridina Milne-Edwards. Rostrum prominent; carpus of first pair 
very short. 
. C. pasadene Kingsley, southern California Fig. 45 
‘Sub-famnily Eirin, 
G. Acanthephyra. Rostrum toothed ; antennulæ biflagellate. 
e : i ‘ i : . A. pacifica (Holmes) Fig. 52 
=- Family PALÆMONIDÆ. 
Sub-family ALPHEINÆ. Second pair of feet usually chelate; carpus 
frequently annulate. 
. Alpheus Fabricius. First pair of feet usually very unequal; carpus 
of second annulat 
ostrum Oo orbital hoods prolonged into spines . ‘ » 49 
48. Rostrum spiniform ; orbital hoods not spined ` : ‘ 2 ks 
48. Rostrum absent; orbital hoods not spined . : ; ; xay 
49. Dactylus of larger pincer normal . ‘ : - í -$0 
49. Dactylus of larger pincer horizontal or iad ; i : s 54 
50. Larger hand with both margins entire . i I $i 
50. Larger hand with margins constricted above oa below. 52 
51. Feet of posterior pairs not spined beneath . A. diunguiculatus Stm. 
(4eviusculus Lockington. Originally descended from PR 
Islands ; may occur on west coast of United States). 
51. Posterior feet spined below . : ‘ . A. minus Say M, S, D 
52. A spine on basal joint of antenna. : : ‘ ‘ : ae 
52. No spine on basal joint of antenna A. websteri Kingsley S, Fig. 13 
53. Dactylus of smaller hand with straight lower margin 
. dellimanus Lockington D 
53. Dactylus of smaller hand with tooth near base 
A. eguidactylus* Lockington D 
54. No spine on basal joint of antenna A. barbara Lockington D 
54. Basal joint of antenna spined A. clamator Lockington D 
55. Basal joint of antenna oe p larger hand constricted above and below 
A. packardii Kingsley S, Fig. 9 
1 Imperfectly known ; larger hand lost. 
